The High-definition Digital Media Interface (HDMI) is widely used as a bidirectional communication interface.
Moreover, a recording/reproducing apparatus is connected to a video display apparatus via a local area network (LAN) in addition to a connection using the HDMI. For example, it is possible to reproduce content held in a recording/reproducing apparatus, that is, video and audio (generally called a program) using a personal computer (PC).
In the connection using an HDMI, the following HDMI Ethernet Channel (HEC) version 1.4 is established following the Consumer Electronics Control (CEC) standard established later. According to the HEC, a control signal is transferable via Audio Return Channel (ARC) version 1.4 and Ethernet (registered trademark).